Observed Phenomenon The interface from a Squeeze Linux router to an ISP cable modem, configured with this line in /etc/network/interfaces, has MTU = 1500. iface eth0 inet dhcp Good; just as expected.
For Lenny, the same /etc/network/interfaces yields MTU = 576. Very odd. This value should exist for a ppp link and not for an eth link. If a D-Link DI-614+ is inserted between Lenny and the cable modem, then MTU = 1500. Background Factors I prefer to keep Lenny on the machine until Squeeze becomes more reliable. Configuration will be more difficult if the D-Link router remains permanently. Failed Solution According to http://www.debian.org/doc/manuals/reference/ch05.en.html#_setting_mtu I adjusted /etc/network/interfaces to this. iface eth0 inet dhcp hostname "joule" pre-up /sbin/ifconfig $IFACE mtu 1500 Still the wrong MTU is set. pe...@joule:~$ ip link show eth0 3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 576 qdisc pfifo_fast state UNKNOW N qlen 1000 link/ether 00:50:ba:52:79:1c brd ff:ff:ff:ff:ff:ff Questions Can anyone explain why the dhcp negotiation in Lenny results in MTU = 576? Is there any practical way to get 1500? Thanks, ... Peter E. -- Google pathology workshop. In ETHNO, click here -> Desktops.OpenDoc "http://carnot.yi.org". -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/171056445.55354.417...@heaviside.invalid